U-Pb Isotopic Data and Ages of Zircon and Titanite from Rocks from the Yukon-Tanana Upland, Alaska

Metadata:

Identification_Information:
Citation:
Citation_Information:
Originator: Jones III, J.V. (ORCID: 0000-0002-6602-5935)
Originator: O'Sullivan, P. (ORCID: 0000-0002-7247-5107)
Publication_Date: 20200826
Title:
U-Pb Isotopic Data and Ages of Zircon and Titanite from Rocks from the Yukon-Tanana Upland, Alaska
Geospatial_Data_Presentation_Form: tabular digital data
Publication_Information:
Publication_Place: Anchorage, Alaska
Publisher: U.S. Geological Survey, Alaska Science Center
Other_Citation_Details:
Suggested citation: Jones III, J.V., and O'Sullivan, P., 2020, U-Pb isotopic data and ages of zircon, titanite, and detrital zircon from rocks from the Yukon-Tanana Upland, Alaska: U.S. Geological Survey data release, https://doi.org/10.5066/P9WWV93S.
Online_Linkage: https://doi.org/10.5066/P9WWV93S
Description:
Abstract:
This data set contains 3 tables containing uranium-lead (U-Pb) isotopic data and crystallization ages of zircon and titanite from igneous, metamorphic, and sedimentary rocks collected from the Yukon-Tanana upland of eastern interior Alaska between 2013 and 2019. Bulk samples of igneous and metamorphic rocks were processed into concentrated mineral separates of zircon and (or) titanite in USGS laboratories in Denver, Colorado, or by Apatite to Zircon, Inc. (A2Z) and analyzed by USGS research scientists at the Stanford-USGS Sensitive High Resolution Ion Microprobe with Reverse-Geometry (SHRIMP-RG) at Stanford University. Bulk samples of sedimentary and metasedimentary rocks were processed into concentrated mineral separates of detrital zircon and analyzed by Apatite to Zircon, Inc. and GeoSep Services (GSS) using laser-ablation-inductively-coupled-plasma-mass spectrometry (LA-ICP-MS) techniques. The 2 data tables (geology_detritalZircon_easternAK_Jones.csv; geology_SHRIMPRGData_easternAK_Jones.csv) accompanying this data release report the isotopic composition of uranium (U) and thorium (Th) measured in each grain, ratios of two isotopes of lead (207Pb and 206Pb) and two isotopes of uranium (235U and 238U), and the age of each grain. A third table (geology_sampleSummary_easternAK_Jones.csv) reports sample locations, rock characteristics, and interpreted ages. The SHRIMP-RG data table (geology_SHRIMPRGData_easternAK_Jones.csv) also reports concentrations of selected trace elements measured in each grain.
Purpose:
This data set was developed from samples collected during geological mapping and research conducted from 2013 to 2019 and funded by the Mineral Resource Program of the U.S. Geological Survey (USGS). U-Pb zircon and titanite dates from igneous and metamorphic rocks aid in the interpretation of the age of original formation (e.g. crystallization age) and/or the timing of metamorphism of rocks with variety of compositions. U-Pb ages of detrital zircon grains aid in the interpretation of where the zircons in the rocks may have originated. The youngest detrital zircon date from any single sample also provides information about the maximum possible depositional age of the host sediment and, therefore, the geologic unit that contains it. Comparison of detrital zircon age populations from different samples test local to regional correlations of geologic units and aids in the reconstruction of geologic histories of large regions. These data are used to understand the geologic history of the Yukon-Tanana upland in eastern Alaska. These data will be used in support of multiple geological maps, reports, and papers that describe the geological framework and mineral resource potential of the region.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2020
Currentness_Reference: publication date
Status:
Progress: Complete
Maintenance_and_Update_Frequency: None planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -147.4
East_Bounding_Coordinate: -140.5
North_Bounding_Coordinate: 65.6
South_Bounding_Coordinate: 63.0
Keywords:
Theme:
Theme_Keyword_Thesaurus: USGS Metadata Identifier
Theme_Keyword: USGS:ASC307
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: geoscientificInformation
Theme:
Theme_Keyword_Thesaurus: USGS Thesaurus
Theme_Keyword: geology
Theme_Keyword: geochronology
Theme_Keyword: uranium-lead analysis
Theme_Keyword: igneous rocks
Theme_Keyword: sedimentary rocks
Theme:
Theme_Keyword_Thesaurus: NASA GCMD Earth Science Keywords Thesaurus
Theme_Keyword: earth science
Theme:
Theme_Keyword_Thesaurus: GeoRef Thesaurus
Theme_Keyword: U/Pb
Theme_Keyword: SHRIMP data
Theme_Keyword: trace elements
Place:
Place_Keyword_Thesaurus: USGS Geographic Names Information System (GNIS)
Place_Keyword: Alaska
Place_Keyword: Fortymile River
Place_Keyword: Sixty Mile River
Place_Keyword: Ladue River
Place_Keyword: Chatanika River
Place_Keyword: Tok
Place_Keyword: Chicken
Place_Keyword: Eagle
Place_Keyword: Fairbanks
Place_Keyword: White Mountains
Place_Keyword: Divide Mountain
Place_Keyword: Taylor Mountain
Place:
Place_Keyword_Thesaurus: None
Place_Keyword: Yukon-Tanana upland
Access_Constraints: None
Use_Constraints:
None. Users are advised to read the metadata thoroughly to understand appropriate use and data limitations.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey, Alaska Science Center
Contact_Person: James V. Jones
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 4210 University Drive
City: Anchorage
State_or_Province: Alaska
Postal_Code: 99508-4626
Country: U.S.A.
Contact_Voice_Telephone: 907-786-7000
Contact_Electronic_Mail_Address: ascweb@usgs.gov
Cross_Reference:
Citation_Information:
Originator: Jones III, J.V. (ORCID: 0000-0002-6602-5935)
Publication_Date: 2015
Title:
Tectonic and metallogenic evolution of the eastern Yukon-Tanana upland, Alaska
Geospatial_Data_Presentation_Form: web page
Series_Information:
Series_Name: Science Portal
Issue_Identification: 389
Publication_Information:
Publication_Place: Anchorage, Alaska
Publisher: U.S. Geological Survey, Alaska Science Center
Other_Citation_Details:
This is a link to the broader USGS Alaska Science Center research project supported by these data. Users will find a description of the research project and links to associated reports, publications, and data products.
Online_Linkage: https://alaska.usgs.gov/portal/project.php?project_id=389
Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
Zircon crystals were run with zircon reference materials (Temora2, MAD, MADDER), and the titanite samples were run with titanite reference materials (BLR1, MMS). The reference materials were analyzed until isotopic fractionation was stable and the variance in the measured 206Pb/238U and 207Pb/206Pb ratios was at or near 1 percent. Reference materials were subsequently analyzed together with unknowns at a regular interval to monitor fractionation throughout the analytical session. All measured isotopic ratios are reported with associated analytical uncertainty at the 1 sigma range. Detailed analytical methods are described in two supplemental files included in this data release (Supplemental_Info_Analytical_Methods_StanfordUSGSSHRIMP.pdf; Supplemental_Info_Analytical_Methods_A2Z_GSS.pdf).
Logical_Consistency_Report:
No unexpected values are found in these data. Blank cells and cells with value -9999 in the data tables indicate values were either notprovided, not measured, or not calculated.
Completeness_Report: This data set is complete; no data were omitted.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
Horizontal position was measured using hand-held GPS units with positional accuracy of 3 meters or less.
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: Apatite to Zircon, Inc.
Publication_Date: 2018
Title: Detrital Zircon Analytical Methods
Publication_Information:
Publication_Place: Moscow, Idaho
Publisher: Apatite to Zircon, Inc. GeoSep Services
Other_Citation_Details:
This is a supplemental PDF document included in this data release. The file name is Supplemental_Info_Analytical_Methods_A2Z_GSS.pdf.
Type_of_Source_Media: pdf file
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2018
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: Supplemental Info Analytical Methods A2Z GSS
Source_Contribution:
Provides detailed description of laboratory methods and data modeling for U-Pb geochronology.
Source_Information:
Source_Citation:
Citation_Information:
Originator: Stanford-USGS SHRIMP-RG Laboratory
Publication_Date: 2019
Title:
Titanite U-Pb geochronology and trace element analytical methods using Stanford-USGS SHRIMP-RG
Publication_Information:
Publication_Place: Palo Alto, California
Publisher: Stanford-USGS SHRIMP-RG laboratory
Other_Citation_Details:
This is a supplemental document included in this data release. The file name is Supplemental_Info_Analytical_Methods_StanfordUSGSSHRIMPRG.pdf.
Type_of_Source_Media: pdf file
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2019
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: SHRIMP-RG Methods
Source_Contribution:
Provides detailed descriptions of laboratory methods and data modeling for titanite U-Pb geochronology.
Process_Step:
Process_Description:
Detrital zircons were separated from bulk sample using lithium polytungstate and a centrifuge. Zircon grains were mounted in epoxy wafers and then ground down to expose the grain interior, and then polished. Isotopic analyses were performed with either a new Wave UP-213 or New Wave YAG 213 laser ablation system in line with Finnigan Element2 magnetic sector, inductively coupled plasma, mass spectrometer (ICP-MS) at Washington State University Geoanalytical Laboratory in Pullman, Washington. Detailed analytical procedures are described in the accompanying document, Supplemental_Info_Analytical_Methods_A2Z.pdf.
Process_Date: 2019
Process_Step:
Process_Description:
Titanite and zircon grains were separated from crushed and ground samples using standard magnetic and heavy liquid techniques, hand-picked under binocular microscope, and mounted in epoxy discs. The mounts were ground to expose the grain interior, further polished, and imaged using back-scattered electron (BSE) imaging on a JEOL 5600 SEM to identify internal grain zonation patterns and to identify any inclusions or other features such as cracks to be avoided during analysis. Titanite U-Pb ages were obtained with the Stanford-U.S. Geological (USGS) Sensitive High Resolution Ion Microprobe with Reverse-Geometry (SHRIMP-RG) at Stanford University. Detailed analytical procedures are described in the accompanying document, Supplemental_Info_Analytical_Methods_StanfordUSGSSHRIMPRG.pdf.
Process_Date: 2019
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Point
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Geographic:
Latitude_Resolution: 0.0001
Longitude_Resolution: 0.0001
Geographic_Coordinate_Units: Decimal degrees
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: GRS 1980
Semi-major_Axis: 6378137
Denominator_of_Flattening_Ratio: 298.257222101
Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: geology_detritalZircon_easternAK_Jones.csv
Entity_Type_Definition:
Table of U-Pb detrital zircon laser-ablation-inductively-coupled-plasma-mass-spectrometry (LA-ICP-MS) data, reporting concentration and isotopic composition of uranium (U) and thorium (Th) measured in each grain, isotopic ratios of lead (Pb) and uranium (U), and the age of each grain calculated from isotope ratios. The table is presented in comma separated value (CSV) format and holds 1491 records.
Entity_Type_Definition_Source: Author defined
Attribute:
Attribute_Label: Sample
Attribute_Definition:
Sample identifier as collected in the field. Descriptive and locational information about the sample is provided in table geology_sampleSummary_easternAK_Jones.csv, and may be linked through attribute Sample.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Unique sample identifier; most labels consisting of the last two digits of the year collected, an abbreviation identifying the collector, and a number and possible suffix.
Attribute:
Attribute_Label: Analysis_Lab
Attribute_Definition: Identifies the lab where analysis was done.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: A2Z
Enumerated_Domain_Value_Definition: Apatite to Zircon, Inc., Moscow, Idaho
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: GSS
Enumerated_Domain_Value_Definition: GeoSep Services, Moscow, Idaho
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute:
Attribute_Label: Lab_Sample
Attribute_Definition:
Laboratory sample identifier assigned by A2Z or GSS. Each sample analyzed by A2Z or GSS has a single, unique lab sample identifier that corresponds to the unique field sample identifier.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain: Hyphenated numeric code assigned by the A2Z or GSS laboratory.
Attribute:
Attribute_Label: Mineral
Attribute_Definition: Material analyzed.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: DZ
Enumerated_Domain_Value_Definition: detrital zircon
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute:
Attribute_Label: Analysis_Name
Attribute_Definition:
A unique identification assigned by the laboratory for an individual analysis. Each analysis represents a single grain from the whole rock sample.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
An alpha-numeric code including a variation of the attribute Lab_Sample.
Attribute:
Attribute_Label: U_conc_ppm
Attribute_Definition:
Concentration of uranium (U) in parts per million (ppm). Value -9999 denotes not measured or not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 10.0
Range_Domain_Maximum: 8081.2
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Th_conc_ppm
Attribute_Definition:
Concentration of thorium (Th) in parts per million (ppm). Value -9999 denotes not measured or not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.2
Range_Domain_Maximum: 2591.0
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: U_Th_Ratio
Attribute_Definition:
The ratio of the concentration of uranium (U) to the concentration of thorium (Th). Value -9999 denotes ratio not calculated due to absence of reported U_conc_ppm and Th_conc_ppm.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.33
Range_Domain_Maximum: 503.75
Attribute:
Attribute_Label: 207Pb_235U_Ratio
Attribute_Definition: Total ratio of 207Pb to 235U.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.0520
Range_Domain_Maximum: 23.8949
Attribute:
Attribute_Label: 207Pb_235U_Ratio_Unc_1sig_abs
Attribute_Definition: Uncertainty (1-sigma) for the ratio of 207Pb to 235U.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.0021
Range_Domain_Maximum: 2.3522
Attribute:
Attribute_Label: 206Pb_238U_Ratio
Attribute_Definition: Total ratio of 206Pb to 238U.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.0079
Range_Domain_Maximum: 0.6196
Attribute:
Attribute_Label: 206Pb_238U_Ratio_Unc_1sig_abs
Attribute_Definition: Uncertainty (1-sigma) for the ratio of 206Pb to 238U.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.0001
Range_Domain_Maximum: 0.1024
Attribute:
Attribute_Label: Error_Correlation
Attribute_Definition: Error correlation of the 207Pb/235U and 206Pb/238U ratios.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.01
Range_Domain_Maximum: 0.84
Attribute:
Attribute_Label: 207Pb_206Pb_Ratio
Attribute_Definition: Total ratio of 207Pb to 206Pb.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.04610
Range_Domain_Maximum: 0.29654
Attribute:
Attribute_Label: 207Pb_206Pb_Ratio_Unc_1sig_abs
Attribute_Definition: Uncertainty (1-sigma) of the ratio of 207Pb to 206Pb.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00069
Range_Domain_Maximum: 0.22340
Attribute:
Attribute_Label: 207Pb_235U_Age
Attribute_Definition:
Age in millions of years calculated from the 207Pb/235U ratio.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 51.4
Range_Domain_Maximum: 3264.1
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: 207Pb_235U_Age_Unc_1sig
Attribute_Definition:
Uncertainty (1-sigma) in millions of years for the age calculated from the 207Pb/235U ratio.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 2.0
Range_Domain_Maximum: 479.4
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: 206Pb_238U_Age
Attribute_Definition:
Age in millions of years calculated from the 206Pb/238U ratio.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 51.0
Range_Domain_Maximum: 3108.6
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: 206Pb_238U_Age_Unc_1sig
Attribute_Definition:
Uncertainty (1-sigma) in millions of years for the age calculated from the 206Pb/238U ratio.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.7
Range_Domain_Maximum: 489.3
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: 207Pb_206Pb_Age
Attribute_Definition:
Age in millions of years calculated from the 207Pb/206Pb ratio.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 3.4
Range_Domain_Maximum: 3452.2
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: 207Pb_206Pb_Age_Unc_1sig
Attribute_Definition:
Uncertainty (1-sigma) in millions of years for the age calculated from the 207Pb/206Pb ratio.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 15.6
Range_Domain_Maximum: 1998.8
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: Preferred_Age
Attribute_Definition:
Preferred age in millions of years selected from one of the three following fields containing calculated ages for each grain: 207Pb_235U_Age or 206Pb_238U_Age or 207Pb_206Pb_Age. Zero values indicate an analysis that failed to yield an age.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 51.0
Range_Domain_Maximum: 3452.2
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: Preferred_Age_Unc_1sig
Attribute_Definition:
Uncertainty (1-sigma) in millions of years for the preferred age. Zero values indicate an analysis that failed to yield an age.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.8
Range_Domain_Maximum: 513.2
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: Preferred_Age_Type
Attribute_Definition:
Method used to calculate the value in Preferred_Age field for each individual analysis that yielded a valid result. Refer to the description of analytical methods, file Supplemental_Info_Analytical_Methods_A2Z.pdf, for more details.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
The following values are used: 206Pb_238U_Age and 207Pb_206Pb_Age
Attribute:
Attribute_Label: Percent_Discordant
Attribute_Definition:
Discordance of 206Pb/238U age versus 207Pb/206Pb age, in percent.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -1450.1
Range_Domain_Maximum: 93.8
Attribute_Units_of_Measure: percent
Detailed_Description:
Entity_Type:
Entity_Type_Label: geology_SHRIMPRGData_easternAK_Jones.csv
Entity_Type_Definition:
Table of U-Pb titanite and zircon SHRIMP-RG data, reporting the isotopic concentration of uranium (U), lead (Pb), and thorium (Th) measured in individual grains, isotopic ratios of Pb and U, and the age of each grain calculated from the isotope ratios. The table also reports concentrations of selected trace elements measured in the same grains. The table contains 1635 records and is presented in comma separated value (CSV) format.
Entity_Type_Definition_Source: Author defined
Attribute:
Attribute_Label: Sample
Attribute_Definition:
Sample number attributed when collected in the field. The value is unique for each sample but is repeated many times in this table because many individual grains from a single sample are analyzed. Descriptive and locational information about the sample is in table geology_sampleSummary_easternAK_Jones.csv, and may be linked through attribute Sample.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Unique sample identifier; most labels consisting of the last two digits of the year collected, an abbreviation identifying the collector, and a number and possible suffix.
Attribute:
Attribute_Label: Mineral
Attribute_Definition: Mineral analyzed
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
The following values are used in this data set: titanite, zircon, and zircon exterior (zircon surfaces).
Attribute:
Attribute_Label: Mount
Attribute_Definition: Internal laboratory ID number for sample mount
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain: Alphanumeric code assigned by the laboratory
Attribute:
Attribute_Label: Standard
Attribute_Definition: Age reference material used on mount
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: BLR1
Enumerated_Domain_Value_Definition: Bear Lake diggings titanite standard
Enumerated_Domain_Value_Definition_Source:
Aleinikoff, J.A., Wintsch, R.P., Tollo, R.P., Unruh, D.M., Fanning, C.M., and Schmitz, M.D., 2007, Ages and origins of rocks of the Killingworth Dome, south-central Connecticut: Implications for the tectonic evolution of southern New England: American Journal of Science, v. 307, p. 63-118, https://doi.org/10.2475/01.2007.04.
Mazdab, F.K., 2009, Characterization of flux-grown trace-element-doped titanite using the high-mass-resolution ion microprobe (SHRIMP-RG): The Canadian Mineralogist, v. 47, p. 813-831, https://doi.org/10.3749/canmin.47.4.813.
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: MMS
Enumerated_Domain_Value_Definition: McClure Mountain syenite titanite standard
Enumerated_Domain_Value_Definition_Source:
Schoene, B., and Bowring, S.A., 2006, U-Pb systematics of the McClure Mountain syenite: thermochronological constraints on the age of the 40Ar/39Ar standard MMhb: Contributions to Mineralogy and Petrology, v. 151, p. 615-630, https://doi.org/10.1007/s00410-006-0077-4.
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: TEM2
Enumerated_Domain_Value_Definition: Middledale gabbroic diorite zircon standard
Enumerated_Domain_Value_Definition_Source:
Black, L.P., Kamo, S.L., Allen, C.M., Davis, D.W., Aleinikoff, J.N., Valley, J.W., Mundil, R., Campbell, I.H., Korsch, R.J., Williams, I.S., and Foudoulis, C. 2004, Improved 206Pb/238U microprobe geochronology by the monitoring of trace-element-related matrix effect; SHRIMP, ID-TIMS, ELA-ICP-MS and oxygen isotope documentation for a series of zircon standards: Chemical Geology, 205, p.115-140, https://doi.org/10.1016/j.chemgeo.2004.01.003.
Attribute:
Attribute_Label: Standard_Age
Attribute_Definition:
Assumed age of age reference material for data reduction, in millions of years (Ma).
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
The assumed ages for the standards are: BLR1 (1047 Ma), MMS (524 Ma), and TEM2 (416.8 Ma).
Attribute:
Attribute_Label: Conc_Std
Attribute_Definition:
Concentration standard used to calibrate trace element concentrations in unknowns.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: BLR1
Enumerated_Domain_Value_Definition: Bear Lake diggings titanite standard
Enumerated_Domain_Value_Definition_Source:
Aleinikoff, J.A., Wintsch, R.P., Tollo, R.P., Unruh, D.M., Fanning, C.M., and Schmitz, M.D., 2007, Ages and origins of rocks of the Killingworth Dome, south-central Connecticut: Implications for the tectonic evolution of southern New England: American Journal of Science, v. 307, p. 63-118, https://doi.org/10.2475/01.2007.04.
Mazdab, F.K., 2009, Characterization of flux-grown trace-element-doped titanite using the high-mass-resolution ion microprobe (SHRIMP-RG): The Canadian Mineralogist, v. 47, p. 813-831, https://doi.org/10.3749/canmin.47.4.813.
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: MAD
Enumerated_Domain_Value_Definition: zircon reference material
Enumerated_Domain_Value_Definition_Source:
Barth, A.P., and Wooden, J.L., 20010, Coupled elemental and isotopic analyses of polygenetic zircons from granitic rocks and by ion microprobe, with implications for melt evolution and the sources of granitic magmas: Chemical Geology, v. 277, p. 149-159, https://doi.org/10.1016/j.chemgeo.2010.07.017.
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: MADDER
Enumerated_Domain_Value_Definition: zircon reference material
Enumerated_Domain_Value_Definition_Source:
Coble, M.A., Vazquez, J.A., Barth, A.P., Wooden, J., Burns, D., Kylander-Clark, A., Jackson, S., and Vennari, C.E., 2018, Trace element characterization of MAD-559 zircon reference material for ion microprobe analysis: Geostandards and Geoanalytical Research, v. 42, p. 481–497, https://doi.org/10.1111/ggr.12238.
Attribute:
Attribute_Label: Analysis_Spot
Attribute_Definition: Internal ID number of individual analysis spot on this Mount.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Alphanumeric code assigned by the analyst. In general, the first number after the sample name indicates the unique grain from an individual sample. The second number indicates the unique spot for each individual grain.
Attribute:
Attribute_Label: AnalysisSpot_Mount
Attribute_Definition: Concatenation of Analysis_Spot and Mount attributes.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Concatenation of Analysis_Spot and Mount attributes separated by an underscore (_).
Attribute:
Attribute_Label: Analysis_Date_Time
Attribute_Definition:
The calendar date and time of the analysis; formatted yyyy-mm-dd, hh:mm.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 2013-11-22, 19:14
Range_Domain_Maximum: 2020-01-10, 19:00
Attribute_Units_of_Measure: yyyy-mm-dd, hh:mm
Attribute:
Attribute_Label: U_conc_ppm
Attribute_Definition:
Uranium concentration, in parts per million (ppm). Value -9999 denotes not measured or not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.065
Range_Domain_Maximum: 4487.114
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Th_conc_ppm
Attribute_Definition:
Thorium concentration, in parts per million (ppm). Value -9999 denotes not measured or not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.000
Range_Domain_Maximum: 15570.182
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: comm_206Pb
Attribute_Definition:
207Pb corrected common 206Pb, in percent. Value -9999 denotes no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -0.002
Range_Domain_Maximum: 182.815
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: 238U_206Pb_Ratio
Attribute_Definition: Total ratio of 238U to 206Pb
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.09
Range_Domain_Maximum: 292.26
Attribute:
Attribute_Label: 238U_206Pb_Ratio_Unc_1sig_perc
Attribute_Definition:
Uncertainty (1-sigma) on total ratio of 238U to 206Pb, in percent
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.55
Range_Domain_Maximum: 203.33
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: 207Pb_206Pb_Ratio
Attribute_Definition: Total ratio of 207Pb to 206Pb
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -0.018
Range_Domain_Maximum: 0.840
Attribute:
Attribute_Label: 207Pb_206Pb_Ratio_Unc_1sig_perc
Attribute_Definition:
Uncertainty (1-sigma) on total ratio of 207Pb to 206Pb, in percent
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.339
Range_Domain_Maximum: 100.354
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: 204Pbcorr_238U_206Pb_Ratio
Attribute_Definition: 204Pb-corrected ratio of 238U to 206Pb
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -14.997
Range_Domain_Maximum: 294.379
Attribute:
Attribute_Label: 204Pbcorr_238U_206Pb_Ratio_Unc_1sig_perc
Attribute_Definition:
Uncertainty (1-sigma) on 204Pb-corrected ratio of 238U to 206Pb, in percent
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.576
Range_Domain_Maximum: 762.705
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: 204Pbcorr_207Pb_206Pb_Ratio
Attribute_Definition: 204Pb-corrected ratio of 207Pb to 206Pb
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.001
Range_Domain_Maximum: 2.232
Attribute:
Attribute_Label: 204Pbcorr_207Pb_206Pb_Ratio_Unc_1sig_perc
Attribute_Definition:
Uncertainty (1-sigma) on 204Pb-corrected ratio of 207Pb to 206Pb, in percent
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.468
Range_Domain_Maximum: 2226.998
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: 204Pbcorr_207Pb_235U_Ratio
Attribute_Definition: 204Pb-corrected ratio of 207Pb to 235U
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -85.391
Range_Domain_Maximum: 195.528
Attribute:
Attribute_Label: 204Pbcorr_207Pb_235U_Ratio_Unc_1sig_perc
Attribute_Definition:
Uncertainty (1-sigma) on 204Pb-corrected ratio of 207Pb to 235U, in percent
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 1.118
Range_Domain_Maximum: 2227.002
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: 204Pbcorr_206Pb_238U_Ratio
Attribute_Definition: 204Pb-corrected ratio of 206Pb to 238U
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -0.679
Range_Domain_Maximum: 2.871
Attribute:
Attribute_Label: 204Pbcorr_206Pb_238U_Ratio_Unc_1sig_perc
Attribute_Definition:
Uncertainty (1-sigma) on 204Pb-corrected ratio of 206Pb/238U, in percent
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.576
Range_Domain_Maximum: 762.705
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: Error_Correlation
Attribute_Definition: Error correlation of 207Pb/235U and 206Pb/238U ratios
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.001
Range_Domain_Maximum: 0.99
Attribute:
Attribute_Label: 207Pbcorr_206Pb_238U_Age
Attribute_Definition:
207Pb-corrected 206Pb/238U age, in millions of years before present (mega-annum)
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -216.33
Range_Domain_Maximum: 3142.76
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: 207Pbcorr_206Pb_238U_Age_Unc_1sig
Attribute_Definition:
Uncertainty (1-sigma) on 207Pb-corrected 206Pb/238U age, in millions of years
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00
Range_Domain_Maximum: 4458.16
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: 204Pbcorr_207Pb_206Pb_Age
Attribute_Definition:
204Pb-corrected 207Pb/206Pb age, in millions of years. Blank cells are present when a calculated age cannot be reported, possibly due to a technical issue or the concentration of 207Pb is low.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -1141.68
Range_Domain_Maximum: 6342.95
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: 204Pbcorr_207Pb_206Pb_Age_Unc_1sig
Attribute_Definition:
Uncertainty (1-sigma) on 204Pb-corrected 207Pb/206Pb age, in millions of years. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 8.45
Range_Domain_Maximum: 31814.00
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: Preferred_SHRIMP_Age
Attribute_Definition:
Preferred grain age for calculation of sample age (in millions of years) selected from one of the two following fields containing calculated ages: 207Pbcorr_206Pb_238U_Age or 204Pbcorr_207Pb_206Pb_Age.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -216.33
Range_Domain_Maximum: 3142.76
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: Preferred_SHRIMP_Age_Unc_1sig
Attribute_Definition:
Uncertainty (1-sigma) in millions of years on preferred grain age
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00
Range_Domain_Maximum: 4458.16
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: Preferred_SHRIMP_Age_Type
Attribute_Definition:
Method used to calculate the values in Preferred_SHRIMP_Age field for each individual analysis that yielded a valid result.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
The only attributes in this data set are 204Pbcorr_207Pb_206Pb_Age and 207Pbcorr_206Pb_238U_Age.
Attribute:
Attribute_Label: Interpreted_Age_Included
Attribute_Definition:
Indication of whether or not analysis was used in the calculation of field UPb_Age_Ma in table geology_sampleSummary_easternAK_Jones.csv. Blanks cells are present; see UPb_Age_Comment in geology_SampleSummary_easternAK_Jones.csv.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Y
Enumerated_Domain_Value_Definition: yes
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: N
Enumerated_Domain_Value_Definition: no
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute:
Attribute_Label: Percent_Discordant
Attribute_Definition:
Discordance of 206Pb/238U age versus 207Pb/206Pb age, in percent. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -99.41
Range_Domain_Maximum: 99.35
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: Y_ppm
Attribute_Definition:
Yttrium concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 9.2
Range_Domain_Maximum: 10939.0
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Nb_ppm
Attribute_Definition:
Niobium concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 232.9
Range_Domain_Maximum: 736.4
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: La_ppm
Attribute_Definition:
Lanthanum concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.000
Range_Domain_Maximum: 2471.888
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Ce_ppm
Attribute_Definition:
Cerium concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.01
Range_Domain_Maximum: 11301.54
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Pr_ppm
Attribute_Definition:
Praseodymium concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.20
Range_Domain_Maximum: 82.70
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Nd_ppm
Attribute_Definition:
Neodymium concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00
Range_Domain_Maximum: 1226.01
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Sm_ppm
Attribute_Definition:
Samarium concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00
Range_Domain_Maximum: 315.80
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Eu_ppm
Attribute_Definition:
Europium concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00
Range_Domain_Maximum: 52.92
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Gd_ppm
Attribute_Definition:
Gadolinium concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00
Range_Domain_Maximum: 553.56
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Dy_ppm
Attribute_Definition:
Dysprosium concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00
Range_Domain_Maximum: 1150.59
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Er_ppm
Attribute_Definition:
Erbium concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00
Range_Domain_Maximum: 2107.16
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Yb_ppm
Attribute_Definition:
Ytterbium concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 2.46
Range_Domain_Maximum: 4493.25
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Hf_ppm
Attribute_Definition:
Hafnium concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 4443.76
Range_Domain_Maximum: 43080.49
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: 48Ti_ppm
Attribute_Definition:
Titanium (from mass 48) concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00
Range_Domain_Maximum: 6668.21
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: 49Ti_ppm
Attribute_Definition:
Titanium (from mass 49) concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00
Range_Domain_Maximum: 6075.55
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Fe_ppm
Attribute_Definition:
Iron concentration in parts per million. Value -9999 indicates no data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00
Range_Domain_Maximum: 10394.30
Attribute_Units_of_Measure: parts per million (ppm)
Detailed_Description:
Entity_Type:
Entity_Type_Label: geology_sampleSummary_easternAK_Jones.csv
Entity_Type_Definition:
Table with descriptive sample information, including location, rock description, and summary of geochronology analyses. This table contains 95 records and is presented in comma separated value (CSV) format.
Entity_Type_Definition_Source: Author defined
Attribute:
Attribute_Label: Sample
Attribute_Definition:
Sample number assigned when sample was collected in the field. This attribute links to field Sample in tables geology_detritalZircon_easternAK_Jones.csv and geology_SHRIMPRGData_easternAK_Jones.csv.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Unique sample identifier; most labels consisting of the last two digits of the year collected, an abbreviation identifying the collector, and a number and possible suffix.
Attribute:
Attribute_Label: Lab_Sample
Attribute_Definition:
Laboratory sample identifier assigned by A2Z or GSS. Same as field Lab_Sample in table geology_detritalZircon_easternAK_Jones.csv. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain: Hyphenated numeric code assigned by the A2Z or GSS laboratory.
Attribute:
Attribute_Label: Latitude
Attribute_Definition: Latitude given in decimal degrees; datum NAD83
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 63.0070
Range_Domain_Maximum: 65.5770
Attribute_Units_of_Measure: decimal degree
Attribute:
Attribute_Label: Longitude
Attribute_Definition: Longitude given in decimal degrees; datum NAD83.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -147.3836
Range_Domain_Maximum: -140.5432
Attribute_Units_of_Measure: decimal degree
Attribute:
Attribute_Label: Rock_Class
Attribute_Definition: Basic rock classification of the sample
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Attributes in this dataset are igneous, metamorphic, and sedimentary.
Attribute:
Attribute_Label: Rock_Type
Attribute_Definition: Sample rock type
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain: General rock description.
Attribute:
Attribute_Label: Rock_Comment
Attribute_Definition:
Additional sample description which may include more detailed rock description, location, geologic map unit.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Additional sample description which may include more detailed rock description, location, geologic map unit.
Attribute:
Attribute_Label: Analysis_Type
Attribute_Definition: Type of geochronologic analysis
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: U-Pb detrital zircon
Enumerated_Domain_Value_Definition: Uranium-lead analysis on detrital zircon
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: U-Pb titanite
Enumerated_Domain_Value_Definition: Uranium-lead analysis on titanite
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: U-Pb zircon
Enumerated_Domain_Value_Definition: Uranium-lead analysis on zircon
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute:
Attribute_Label: Analysis_Lab
Attribute_Definition: Laboratory or contractor responsible for the analysis
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: A2Z
Enumerated_Domain_Value_Definition: Apatite to Zircon, Inc., Moscow, Idaho
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: GSS
Enumerated_Domain_Value_Definition: GeoSep Services, Moscow, Idaho
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Stanford-USGS SHRIMP-RG
Enumerated_Domain_Value_Definition:
Stanford-USGS Sensitive High Resolution Ion Microprobe with Reverse Geometry
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute:
Attribute_Label: Analysis_Method
Attribute_Definition: Laboratory equipment and methodology used to collect data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: LA-ICP-MS U-Pb
Enumerated_Domain_Value_Definition:
Laser ablation inductively coupled plasma mass spectrometry techniques for U-Pb
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: SHRIMP U-Pb
Enumerated_Domain_Value_Definition:
Sensitive high-resolution ion microprobe with reverse geometry for U-Pb
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute:
Attribute_Label: UPb_Age_N_Grains_Total
Attribute_Definition: Total number of grains analyzed. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 3
Range_Domain_Maximum: 70
Attribute:
Attribute_Label: UPb_Age_Ma
Attribute_Definition:
Weighted average age calculated for sample in millions of years. Blanks cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 79.4
Range_Domain_Maximum: 375.7
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: UPb_Age_Unc_Ma
Attribute_Definition:
Uncertainty (2-sigma) of weighted average age calculated for sample, in millions of years. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 1.1
Range_Domain_Maximum: 16.0
Attribute_Units_of_Measure: millions of years
Attribute:
Attribute_Label: UPb_Age_Method
Attribute_Definition:
Method used to calculate the value in UPb_Age_Ma. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
The only attributes in this data set are 'weighted average of 206Pb/238U age' and 'isochron intercept'.
Attribute:
Attribute_Label: UPb_Age_N_Grains
Attribute_Definition:
Number of analyses used to calculate the value in UPb_Age_Ma. Blanks cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 4
Range_Domain_Maximum: 44
Attribute:
Attribute_Label: UPb_Age_MSWD
Attribute_Definition:
Mean square of weighted deviates for calculated value in UPb_Age_Ma. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.14
Range_Domain_Maximum: 2.50
Attribute:
Attribute_Label: UPb_Age_Comment
Attribute_Definition: Comments on the sample age or analytical observations.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain: Comments on the sample age or analytical observations.
Attribute:
Attribute_Label: UPb_Age_Interpretation
Attribute_Definition:
Geological significance of the interpreted age. Blank cells when there is no age determination.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: crystallization
Enumerated_Domain_Value_Definition:
A crystallization age indicates growth of the dated mineral grains during original formation of the rock.
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: metamorphism
Enumerated_Domain_Value_Definition:
A metamorphic age indicates growth and (or) recrystallization of the dated mineral grains during metamorphism.
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: detrital
Enumerated_Domain_Value_Definition:
Indicates that all of the dated grains are detrital in nature and formed prior to incorporation into the rock.
Enumerated_Domain_Value_Definition_Source: Author defined
Detailed_Description:
Entity_Type:
Entity_Type_Label: geology_dataDictionary_easternAK_Jones.csv
Entity_Type_Definition:
Table listing the name of all fields in each table, with a brief description of the field and the data units, if applicable.
Entity_Type_Definition_Source: Author defined
Attribute:
Attribute_Label: Table
Attribute_Definition: Name of the data table the field is found in.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
The data tables in this data set include geology_detritalZircon_easternAK_Jones.csv, geology_SHRIMPData_easternAK_Jones.csv, and geology_sampleSummary_easternAK_Jones.csv.
Attribute:
Attribute_Label: Field
Attribute_Definition: Field name found in data table listed in field Table
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
The field names are single words or concatenated abbreviations that describe the contents of the field.
Attribute:
Attribute_Label: Description
Attribute_Definition: Brief description of the contents of the field
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain: Brief description of the contents of the field
Attribute:
Attribute_Label: Units
Attribute_Definition: The unit of measurement for applicable data fields
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: %
Enumerated_Domain_Value_Definition: percent
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: degree
Enumerated_Domain_Value_Definition: unit of angle measurement
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Ma
Enumerated_Domain_Value_Definition: mega-annum or million years
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: n/a
Enumerated_Domain_Value_Definition: not applicable
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: ppm
Enumerated_Domain_Value_Definition: parts per million
Enumerated_Domain_Value_Definition_Source: Author defined
Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey, Alaska Science Center
Contact_Address:
Address_Type: mailing and physical
Address: 4210 University Drive
City: Anchorage
State_or_Province: Alaska
Postal_Code: 99508-4626
Country: U.S.A.
Contact_Voice_Telephone: 907-786-7000
Contact_Electronic_Mail_Address: ascweb@usgs.gov
Resource_Description:
The USGS ASC Repository is the Authoritative source for this data.
Distribution_Liability:
Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: CSV
Format_Information_Content:
Data are distributed in a Zip package containing data in CSV format, FGDC metadata in XML and HTML formats and supplementary information about laboratory methods in PDF format.
File_Decompression_Technique:
Compression applied by the 7-Zip utility using default compression (5). The file can be decompressed and unpacked by open source or commercially available unzip tools.
Transfer_Size: 1.00
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name: https://doi.org/10.5066/P9WWV93S
Fees: None
Metadata_Reference_Information:
Metadata_Date: 20201125
Metadata_Review_Date: 20200727
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey, Alaska Science Center
Contact_Address:
Address_Type: mailing and physical address
Address: 4210 University Drive
City: Anchorage
State_or_Province: Alaska
Postal_Code: 99508-4626
Country: U.S.A.
Contact_Voice_Telephone: 907-786-7000
Contact_Electronic_Mail_Address: ascweb@usgs.gov
Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Generated by mp version 2.9.50 on Tue Aug 25 17:38:54 2020